Chamfering tool



April 10, 1945. D. HEYER I CHAMFEHING TOOL Filed Oct. 14, 1942 Patented Apr. 10, 1945 UNITED STATES 2,373,474 CHAMFERING TOOL Don Heyer, Los Angeles, Calif. Application October 14, 1942, Serial No. 461,966

20 Claims. (01. 77-73) This invention relates to metal working tools, and more particularly to tools for finishing, chamfering, counter-sinking and spot facing in conjunction with bored, drilled or reamed holes.

The production of holes through metal or analogous substances usually results in sharp corners or even projecting edges which are commonly referred to as burrs. When milling a surface which extends across a bore the milling cutter produces sharp edges or burrs at the junction between the walls of the bore and the finished surface produced. It is common practice to require that the sharp edges or burrs in metal be removed regardless-of how they are produced. In the past this has been done by the use of a file or scraper, or by means of grinding.

There are several situations in which the conventional tools for breaking the edge or remov ing the burr around an opening will not satisfy. When a drilled, reamed, or bored hole extends completely through a metal structure removal of the burrs from both ends of the bore is usually desirable. Oftentimes it is also desirable to spotfac the surface adjacent each end of the hole. The exigencies of design, such as multiple-walled parts where several aligned holes are drilled or reamed through closely spaced walls, oftentimes leaves insufficient room for easy removal of the burr on all the surfaces of the work.

It is an object of the present invention to provide a. tool for spot-facing, counter-sinking, or

chamfering having a cutter that can be readily inserted through a bore and projected during rotation of the tool to perform the operation.

It is another object of the invention to prevent the inadvertent projection of the blade during its passage through the bore.

A further object of the invention is the provision of means for positively holding the blade in operative position.

It is an object of the present invention to pro vide a device for spot-facing, counter-sinking or chamfering, which can be readily passed through a bore and operated at either end thereof to perform the finishing operation.

It is an object of the present invention to provide a device which may be readily incorporated in a boring, drilling or reaming tool, and which will be adapted to the counter-sinking, chamfering or spot-facing of the work being operated upon.

It is a further object of the present invention to provide a device for spot-facing, chamfering, or counter-sinking in which the cutting element can be readily removed from the holder.

1 ATENT OFFICE It is a further object of the presentinvention to provide a spot-facing, counter-sinking or chamfering toolwhich normally does not interfere with the reaming operation.

This invention possesses many other advantages and has other objects which may be made more easily apparent from a consideration of one embodiment of the invention. For this purpose there'is shown a form in the drawing accompanying and forming part of the present specification. This form will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawing:

Figure 1 is a view partly in section, showing one form of the present invention in which the chamfering device is incorporated in a reamer;

Figure 2 is a transverse section taken along line 2-2 of Figure 1; and

Figure 3 is a transverse section taken along line 3-3 of Figure 1.

Referring in particular to Figure 1, an elon-j gated body member ID is provided with reamer blades H at one end and a shank portion l2 at the opposite end by which the tool may be held in a chuck or the like and rotated, or stationarily held while the work is revolved. Within the body l0 there'is provided an elongated slot l3. This slot is shown as having a bottom which is curved at both ends as at M and I5 for purposes which will presently appear. An elongated cutter element I6 is slidably contained in the slot [3 and carries on one end thereof a cutting blade ll. This cutting blade l1 may be provided with cutting edges of any form desired depending upon the function to be performed by it. In the shown form, the cutting blade I! is intended for chamfering the ends of the bores reamed by the reaming blades H. As it is desired to chamfer both the top and bottom of the holes produced, the blade I! has its edge l8 and its edge l8 suitably formed to perform this function. It can be readily seen that if the blade I! is in the projected position shown in light broken lines, Figure 1,

it will chamfer the edge of a hole when the entire tool is moved axially in either direction.

As it is desired to be able to chamfer the bottom edge of a hole reamed by the reamer II, it is necessary that the cutting blade I! be retractable from the projected position shown in light broken lines. In order to retract the tool,

and at the same time permit its positive support portion I5 of the slot in the projected position, the structure shown on the right hand end of Figure 1 is employed. This structure comprises a collar I9 mounted on the elongated body ID for sliding movement longitu-- dinally thereof. The interior of the collar is provided with a slot 20 which is in alignment With the slot I3 in the body I and receives the end of the elongated cutter element I6 opposite the end upon which the blade I! is mounted, The entire cutter element I6 cooperates with the curved bottom portions of the slot I3 and with the collar I9 in such a manner that movement of the collar axially of the body I 0 will result in projection and retraction of the blade I! in a positive manner.

'As can be seen in Figure 1, the cutter element I 6 is curved at I511 to substantially fit the bottom curve I of the slot I3. A pivot pin-22in the left from the solid line position in Figure 1, the engagement between the curved portion I5 of the bottom of the slot I3 and the corresponding curved portion lid of the cutter element I6 is broken. Thus, the blade I! would be free to move outwardly under the influence of centrifugal force but for the spring 25, which is of suflicient strength to prevent such movement. The use of a spring 25 also permits ready removal of the cutter element I6 for sharpening the blade I! or for replacement. It is merely necessary to move the collar I 9 to a position to the left of that shown in i Figure 1 in solid lines, and press downwardly upon the free end of the spring 25 to release the collar I9 extends through the slot of the collar and engages a notch 23 in the upwardly'extending portion 24 of the cutter element IS. The end of the cutter element I 6 is yieldingly' held against the pivotpin 22 by a .springmounted on the collar I9. This spring isshown as being of a more or less circular configuration, having one end secured to the collarby a pin 2I and the other end engaging a notch 26 in'theunderside of the cutter element I6 to one side of thepivot pin.

The cooperation between the pivot pin 22, the

sh'ape'lof the bottom of the cutter element I6, and

the shape of the slot I3 is such, that reciprocationjof the collar I9 on the body I0 results in'the Projection and'retraction of the blade I'I. Thus, when the collar I9 is moved to the left from the solid line position, Figure 1, the blade carrying end of the cutter element I6 slides over the curved portion I4 of the slot I3, causing a projection of the blade beyond the outer surface of the elongated member III. The projection of the blade I! is limited by the engagement of the collar I9 with an abutment ring 30 on" the elongated body ID;

The limit of the proj'ection-canbe varied by adlusting the abutment ring longitudinally of the body II), which is made possible by the set screw 3|. It can be seen, that when the blade I I is in the projected position shown in light broken lines, a,portion oi the cutter element I Gbeneath the blade bears' against the curved portion I 4 of the slot. I3, thereby rigidly supporting the blade during the cutting operation on' the work.

iWhen the collar is movedback to the right, the reengagement of the curvedportion'l5a of the cutter elementIS with'the curved portion I5 of the bottom of the slot I3, causes a positive retraction of the blade IT. This can be more readily appreciated by considering'the'iact' that a normal drawn from the center-of the pin 22 to the curved I 3 is the shortest distance fromthat center'to the bottom of the slot I 3.

'The engagement oi? the bottom of the slot and the corresponding surface of the cutter element I6 to'the right of the point where the normal meets the curve bottom tends to turn the element I6 about the pin 22 in a counter-clockwise direction.' Thus it"is impossible for centrifugal force to lift the cutter element I6 and blade I1 out of the position shownin solid lines in'Figure 1.

The spring 25, cooperates with the pin 22 to perform all the functionsof holding the cutter element'l 6 and its blade in place in the assembly.

'In addition to this it-serves the: important function of preventing the cutter element I6 from fiying'ou'twardly under the 'influence of centrifugal force duringmovement' of said element between its two extremepositions-of adjustment. For instance, when the collar I9 is moved to the entire element from the influence of the spring and the pin 22. The cutter element I6 can then be slid out from the slot in the collar and removed. Inasmuch as the collar I9 is intended to be reciprocated while the tool is in motion it is desirable to provide a second collar 33 surrounding the collar I 9. This second collar 33'is mounted for rotation with respect tothe collar I9 by means of the balls 34 running in races inthe two collars. This outer collar 33 may be safely grasped in the hand of the operator during rotation of the tool in order to produce the axial movement of the collar I9 for projection or 're- 7 traction of the blade I1.

As it is desired to prevent the blade I! from moving outwardly into engagement with the walls of a bore during its passage therethrough, the collar I9 is provided with a snap catch to hold it in the position shown in solid lines. This snap catch can be in the form of a small ball 36 which 'is forced into a depression in the member ID by a spring 31 contained within a bore in the collar I9. This snap catch positively holds the collar I9 and cutter element I6 in retracted posiftion. It can be seen that so long as the ball 36 is in the depression 35 it is impossible for the blade I I to move outwardly and mar the work, because of the engagement of the bottom of the cutter element I6 with the curved portion I5 of the bottom of th slot I 3. If desired, a seconddepression 38 may be provided in the elongated member III to receive the ball 36 and positively hold the collar I9 and the cutter element I 6 in projected position. 7

I claim:

1. A'tool for chamfering and the like comprising, a body adapted for insertion through a bore,

a cutting blade mounted on said body for movement between a position shielded within the body and a cutting position exterior of the body, means including a member freely rotatably with respect to the body, said member being adapted to move said blade between said positions during rotation of said tool, and means locking said blade in at least one of said positions. 1

2. A tool for chamfering and the like comprising, a body adapted for insertion through a bore, said body having a slot therein, a surface of said slot having portions oppositely inclined with respect to the axis of the body, a cutter element having a blade adapted to be shielded within'said slot, and means causing relative movement between said cutter element and said inclined surfaces to project said blade from the slot or to retract the blade within the slot in accordance with the direction of movement.

3. A tool for chamfering and the like comprising, a body adapted for insertion through a bore, said body having a slot therein, a surface of said slot having portions oppositely inclined with rewithin the slot, said s'pect'tothe axis of the body, a cutter element havingja blade adapted to be shielded'within said slot, means causing relative movement between said cutter element and said inclined surfaces to project said blade from the slot or to retract the blade within the slot in accordance with the direction of movement, and means positively holding said cutter element in shielded position.

' 4. A tool for 'chamfering and the like comprising; a body adapted for insertion through a bore, said body having a slot therein, a surface of said slot being inclined with respect to the axis of the body, a cutter element having a blade shielded ,within said slot, aid cutter element having a portion engageable with said inclined. surface to project the blad from the slot, and means moving said blade into retracted position within said 'slot upon movement of said cutter element out of I engagement with said inclined surface.

5.'A tool for'chamfering and the like comprising, a body adapted for insertion through a bore. said body having a slot therein, a surface of said .slot having axially spaced portions oppositely inclined with respect to the axis of the body, a cutter element having a blade, and means causing relative movement between said cutter element and said inclined surfaces, movement in one direction serving to project said blade from the slot, one of said surfaces positively supporting said blade in projected position, movement in the opposite direction serving to retract the blade within the slot, the other surface cooperating with said means to positively maintain the blade in retracted position.

6. A tool for chamfering and the likecomprising, an elongated body adapted for insertion through a bore, a member mounted on said body for relative axial movement with respect thereto,

a cutter element pivotally mounted on said mem-v ber and having a blade shielded within said body, and means on said body cooperating with said cutter element to move said blade from a shielded to a cutting position upon relative axial movement between said member and said elongated body.

'7. A tool for chamfering and the like comprising, an elongated body adapted for insertion through a bore, said body having a slot therein. a member mounted on said body for relative axial movement with respect thereto, a cutter element pivotally mounted on said'member and having a blade shielded within the slot, and means in said slot projecting said blade from the slot upon' relative axial movement between said elongated body and said member.

8. A tool for chamfering and the like comprising an elongated body adapted for insertion through a bore, said body having a slot therein, a surface of said slot being inclined with respect to the axis of the body, a member mounted on said body for relative axial movement with respect thereto, a cutterelement pivotally mounted on said member and having a blade shielded cutter element having a portion engageable with the inclined surface of said slot to project the blade from the slot upon relative axial movement between said member and said elongated body, said inclined surface positively supporting the position.

9. A tool for chamfering and the like comprising an elongated body adapted for insertion through a bore, said body having a slot therein,

a surface of said slot being inclined with respect blade in said projected l having a cutting blade,

opening toward said blade, and means connecting spect thereto, a cutter element pivotally mounted on said member and having a blade shielded Within the slot, said cutter element having a surface on one side of its pivot engageaolewith the inclined surface of the slotto project the blade therefrom upon movement of the member, and means'onthe elongated body positively retracting the blade into the slot upon movement of the member in the opposite direction.

, 10. A tool for chamfering and the like comprising an elongated body adapted for insertion through a bore, said body having a slot therein, the ends of said slot having surfaces inclined with respect tothe axis of the body, mounted on said body for relative axial movement with respect thereto, a cutter element pivotally mounted on'said member and having a blade shielded within the slot, said cutter'element having a surface on one side of its pivot engageable with one inclined surface of the slot to project the blade therefrom upon movement of the member in one direction and another surface on the opposite side of the pivot engageable with the other inclined surface to positively retract the in the opposite direction.

11. A tool for chamfermg and the like comprising an elongated body adapted for insertion through a bore, said body having a slot therein. said slot having a surface inclined with respect to the axis of the body, a member mounted on said body for relative axial movement with respect thereto, a cutter element pivotally mounted on said member and having a blade shielded within the slot, said cutter element having a surface on one side of its'pivot engageable with the inclined surface of the slot to project the blade therefrom upon movement of the member in one direction, and spring'means acting on said cutter element urging said blade into retracted position.

12. A tool for chamfering and the like comprising, an elongated body adapted for insertion through a bore, said body havinga slot therein,

a surface of said slot being inclined with respect to the axis of the body, a member mounted on said body for relative axial movement with respect thereto, a cutter element having a blade, a pivotal connection between said cutter element and said member resisting displacement of the cutter element in one direction, spring means yieldingly resisting displacement of the cutter element in the opposite direction, said cutter element having a portion engageable with the inclined surface of the slot to project the blade from within the slot upon relative axial movement between said member and said elongated body.

13. In a tool for chamfering and the like, an elongated body collar encircling said body and movable axially therealong, said collar also having an axial interior slot, a cutter element within said slots and the slot in said collar said cutter element to said collar for movement axially of said body upon movement of said collar.

14. In a tool for chamfering and the like, an elongated body having an axial slot therein, a collar encircling said body and movable axially with respect thereto, said collar having a slot interiorly thereof, a cutter element in said slots, cooperating abutting surfaces on said cutter and said collar preventing relative axial movement a member having an axial slot therein, a

elongated body,

of, said collar elongated body, means connecting said cuttereletainsaid abutting surfaces inoperative engage,- ment but yieldable ;in a direction to permit disengagement of saidsurfaces and'removal of said cutter element from the-slots. V

. 15 In a 'toolfor chamfering and thevlike 'an elongated body having an .axialslot therein, a

. collar encircling said body and movable axially with respect thereto, said collar havingea slot interiorly thereof, a-cutter element in said slots, means for releasablycon necting said cutter element to said collar for :pivotal inovement, said meansv comprising complementary pivot surfaces on said cutter element-and the interior. offthe collar slot and spring means actingon saidcutter element to normally-maintain said surfaces in operative engagement but yieldable topermit then-disengagement andremoval of the cutter element from the slots. i 1 Y. .7

16. In a tool for chamfering and the like, an

elongated body, a cutter element mounted on. said body for movement axially thereof, :a collar mounted-on said body, for movement axially thereof, said collar being non-rotatable relative to said;elongatedwbody, means connecting said cutter elementlto said collar for moving. saidvcutter element in response to movement of said collar, and a sleeve rotatably mounted on said collar.

17. In a tool for-chamfering and the (like, an a'cutter element mounted on said body for movement axially, thereof, a collar mounted on said body for-movement axially therebeing non-rotatable relative to said ment to aid collar for movingsaid cutter element in-response-to movementiof saidkcollar, and cooperative means on said collar and said elongated body for positively holding said collar in position axlallyof said elongated member.

18. In a tool forichamfering or the like; an elongated body, a cutter element mounted on ment with respect thereto,

ed on said body for axial attest-4 .therebe weeni: andwnr n means io qsai eep e saidnbody for movement axially thereof a collar acting on said-,cutters ent tq'nq llr i hmduntedlon'saidbo dy for movement axially there'- of, means connecting s'aid'cutter element to said collar formoving said cutter elementin response to movement of said collar, and a pring actuated element in said collar cooperatively engaging a depression in said body for holding said collar in adjusted axial position.

19. A tool for chamfering and the like comprising, an elongatedbody adapted for insertion through a bore, said body having a slot therein, the ends of the slot having surfaces inclined oppositely with respect to the axisof the body,,a member mounted on said body for axial movea cutter element mounted in said slot for axial movement of the bodyand having a blade adapted to be shielded within the slot, means operatively connectingsaid member and said cutter element, said cutter element having surfaces ,adjacentits end portions respectively engageable with said inclined surfaces, engagement of one .of said surfaces with one of said inclined surfaces, inresponse tornovementof said member in one direction serving to project the blade from th slot,:and engagement of the other of said surtaces w'th the other inclined surface in response to movement of said member inthe other direction serving to re'tract h blade nt t e p I 20. A tool for chamfering'and thelikepcomprising a body adapted for insertion through a bore, a cutter element having a blade and mount movement with respect thereto, and spaced cooperative complementary means respectively on "the body and cutter element for projecting the blade in response to relative movement between the cutter-element and the body in one direction and for retracting the blade in response to relative movement-between the cutter element and the body in the opposite direction. V H

' "DONHEYER; 

